This invention relates to new catalysts useful for the preparation of polyamides. More particularly, this invention relates to the polymerization of at least one of an alpha, beta-unsaturated carboxylic acid and ammonia, an ammonium salt of an alpha, beta unsaturated carboxylic acid, an alpha, beta-unsaturated nitrile and water, a beta-amino propionic acid or its alkyl derivatives and an alpha, beta-unsaturated amide and ammonia in the presence of a catalyst comprising a pentaammine cobalt (III) complex.
It is known that polyamides can be prepared from various monomers. For example, U.S. Pat. No. 4,283,524 describes a process wherein polyamides are prepared from the ammonium salts of alpha, beta unsaturated moncarboxylic acids. U.S. Pat. No. 2,691,643 teaches that polyamides can be prepared by the thermal condensation of beta-amino propionic acid. U.S. Pat. Nos. 3,629,203 and 3,499,879 relate to the preparation of polyamides by the condensation reaction of acrylonitrile. U.S. Pat. No. 2,749,331 teaches that polyamides can be prepared from acrylamide. However, each of these processes is deficient in that the polyamide produced has very low molecular weight.
It is an object of this invention to provide a novel catalytic process to produce polyamides which have a high degree of polymerization. Moreover, by using a catalyst system in the reaction, the rate of the polymerization reaction is remarkably increased and the reaction period is greatly shortened.